Pillow block for vibratory shafts



Jan. 20, 1959 F. E. HUTCHISON PILLOW BLOCK FOR VIBRATORY SHAFTS Filed April 1:6, 1954 Fro/714' f. Hufc/zflson INVENTOR.

BY A

ATTORNEY I "W" am air nited States This invention relates to pillow blocks or bearings and particularly to pillow blocks or bearings employed to support shafts or shaft housings which are subjected to extensive vibratory action.

In various types of classifiers, sorters and separators, and the like, drive means are employed to impart vibratory or oscillatory movement to screens, sieves and the like. other vibrating or oscillating elements through which the vibratory or oscillatory movement is imparted to such screens and the like and such shafts will ordinarily be supported in pillow blocks or bearings secured to the screen frame or other structure to be vibrated or oscillated.

One type of pillow block employed for the described purpose employs a resilient liner constructed of rubber or rubber-like material, through which vibratory movement is transmitted to a screen frame or the like by a vibrating shaft supported in the pillow block. Pillow blocks of this particular type are commonly employed with the vibrating screens of so called shale shakers employed in the oil well drilling industry. I

Resilient pillow blocks of the class described are subject to severe and deleterious over heating as a result of the repeated and high frequency flexing produced by the vibratory movement of the vibratory shaft supported by these blocks.

The present invention, therefore, is directed to animproved pillow block for vibratory shafts and the like which will obviate the undesirable results noted above.

I have found that the deleterious overheating of resilient pillow blocks can be overcome by providing a plurality of passages extending entirely through the resilient body, preferably generally parallel to the central axis of the body. By providing such passages, it is found that deflection of the resilient body by the vibration of the supported shaft produces a contraction and expansion of the passages, resulting in a pumping or breathing action, by which atmospheric air will be forced through the passages and thereby cool the pillow block. It will be evident that the more rapid the vibratory movement, the greater the volume of cooling air will be forced through the pillow block, and hence the greater the cooling action, which will thereby be made substantially self-regulating.

Accordingly, a primary object is to provide a selfcooling resilient pillow block especially adapted for vibratory shafts.

A further object is to provide a resilient pillow block having a plurality of breather passages extending therethrough.

An additional object is to provide a pillow block including an annular, segmental metallic housing, and an annular liner of flexible resilient material mounted in the housing, the liner being provided with a plurality of angularly spaced passages extending entirely through the body of the liner generally parallel to the central axis of the liner.

Such drive means frequently employ shafts oratent ice,

Other and more specific objects and advantages of this invention will become more readily apparent from the following detailed description when read in conjunction with the accompanying drawingwhich illustrates useful embodiments in accordance with this invention.

In the drawing:

Fig. l is a fragmentary view, partly in section, of an end portion of a vibratory shaft supported in a pillow block constructed in accordance with one embodiment of this invention; a

Fig. 2 is an enlarged end view of the pillow block, the view being taken generally along line 22 of Fig. 1, the vibratory shaft structure being shown in cross-section;

Fig. 3 is a transverse sectional view taken along line 33 of Fig. 2; and

Fig. 4 is a fragmentary end elevational view of a pillow block in accordance with another embodiment of this invention.

Referring to the drawing, Fig. 1 illustrates a' fragmentary portion of the drive elements of a vibratory device such as a shale-shaker commonly employed for screening oil well drilling muds. The structure shown includes a pillow block constructed in accordance with the present invention and designated generally by the numeral 5, the pillow block being shown secured to a structural support member 6 which may be a frame element of the shaker screen, the details of which form no part of the present invention. Pillow block 5 supports a tubular housing 7 which encloses a drive shaft 8 which is eccentrically journalled for rotation in bearings 9 supported in the bore of housing 7. The end of shaft 8 extends through a closure cap 10 on the end of housing -7 and carries a pulley 11 through-which the shaft 8 is driven from a power source (not shown). It will be understood that rotation of the eccentrically journalled shaft 8 will produce an oscillatory or vibratory movement of housing 7 .casing composed ofcomplementary semi-circular segments 12 and 13, the opposite ends of the segments being equipped with registering bolt ears 1414-adapted to receive bolts 15 for securing the segments together. Lower segment 13 is equipped with feet elements or flanges 16 by which the casing may be securely bolted to frame element 6. The segments are channel shaped in cross section, the opposite edges of the segments being provided with integral vertically disposed annular side flanges 17-17 enclosing between them the channel 18 and defining the axial bore 19 through the casing. Mounted in channel 18 is a liner 20 having a bore 21. The liner may be composed of two complementary semicircular segments positioned in the respective casing segments. Liner 20 is constructed of flexible resilient material, such as natural or synthetic rubber or rubber like composition. The diameter of bore 21 is made smaller than that of bore 19 so that the liner segments will protrude radially inwardly from channel 18 in the casing segments and bear against the exterior of housing 7. The protruding portion is provided on the opposite side edges with laterally projecting annular lips 22 which extend along housing 7 beneath the innercircumferential ends of flanges 17 which define bore 19 and are adapted to be compressed between the flange ends and the exterior of housing 7 when the casing segments and the liner segments are closed about housing 7.

Liner 20 is provided in the wall of bore 21 with a plurality of notches 23, generally arcuate in cross-section, which extend transversely entirely through the width of the liner generally parallel to each other and to the pillow block axis. Notches 23 open to the exterior of the pillow Patented Jan. 20, 1959 3 block through the outer ends of lips 22 and form breather passages for the movement of air therethrough in a manner to be subsequently described.

The pillow block, constructed as above described, operates in the following manner:

When eccentric shaft 8 is rotated, housing 7 is caused to oscillate or vibrate radially with respect to the central axis of the pillow block. The radial oscillatory movement will alternately apply radial pressure to, and thereafter relax the pressure on, the body of liner 20, thereby alternately squeezing together and relaxing the walls of notches 23, with consequent alternate sucking in and squeezing out of atmospheric air through the notches. Since the oscillatory pressure will move around the circumference of the liner as shaft 8 rotates, every segment of the liner will be subjected to this air-breathing and consequent cooling action. The more rapid the oscillation, the greater the volume of air thus pumped through the body of the liner and this air will carry off the heat generated in the liner body by the flexing of the liner and thereby cool the liner and protect it effectively against over-heating.

Fig. 4 illustrates a modified embodiment in which the breather passages are holes 24 extending through the body of the liner positioned so as to be spaced slightly from the wall of bore 21. This arrangement will be found equally effective for cooling the pillow block.

The shapes and number of the air passages may be varied widely and obviously various other changes and modifications may be made in the details of the illustrative embodiments within the scope of the appended claims but without departing from the spirit of this invention.

What I claim and desire to secure by Letters Patent is:

1. A pillow block for vibratory shafts, comprising, an annular metallic casing, an annular non-metallic flexible resilient liner concentrically mounted in the casing and having a bore adapted to'receive in tight flexible engagement 'a vibratory housing, the body of said liner having a plurality of circumferentially spaced passages extending longitudinally through the liner body spaced slightly from the wall of said bore and opening through the ends of the liner body exteriorly of the casing.

2. A pillow block for vibratory shafts, comprising, an annular metallic casing, inwardly extending annular edge flanges on opposite sides of said casing defining between them an annular channel interiorly of the casing, an annular non-metallic flexible resilient liner concentrically seated in said channel and dimensioned to project radially inwardly with respect to the inner ends of said flanges, said liner having a bore adapted to receive in tight flexible engagement a vibratory housing, the body of said liner having a plurality of circumferentially spaced pass-ages extending longitudinally through the liner body spaced slightly from the Wall of said bore, the ends of said passages opening to opposite sides of the liner body beneath the inner ends of said flanges exteriorly of said casing.

3. A pillow block for vibratory shafts, comprising, an annular metallic casing, inwardly extending annular edge flanges on opposite sides of said casing defining between them an annular channel interiorly of the casing, an annular non-metallic flexible resilient liner concentrically seated in the channel and dimensioned to project radially inwardly with respect to the inner ends of said flanges, said liner having a bore adapted to receive in tight flexible engagement a vibratory. housing, annular lips projecting laterally from the opposite ends of said'liner to extend between the inner ends of said flanges and the exterior of said housing, the body of said liner having a plurality of circumferentially spaced passages extending longitudinally through the liner body adjacent the wall of said bore and opening through the outer ends of said lips.

4. A pillow block as defined by claim 3 wherein said passages comprise radial notches in the wall of said bore having their open sides closed longitudinally by the surface of the received housing.

5. A pillow block as defined by claim 3 wherein said casing is constructed of two complementary semicircular segments, and means for separably securing the segments together.

References Cited in the file of this patent UNITED STATES PATENTS 1,483,903 Masury Feb. 19, 1924 2,189,117 Prentice Feb. 6, 1940 2,324,863 Merchant July 20, 1943 2,397,124 Buflington Mar. 26, 1946 2,465,785 Berno Mar. 29, 1949 2,580,119 Meyers Dec. 25, 1951 2,652,293 Phillips Sept. 15, 1953 2,663,599 Mackay et al. Dec. 22, 1953 

